问题描述
引用：
这对我有意义。但是为什么Django使用元组而不是列表进行设置？示例：
This makes sense to me. But why does Django use tuples and not lists for settings? Example:
INSTALLED_APPS = (
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.sites',
'django.contrib.messages',
'django.contrib.staticfiles',
)
这不是（和所有其他设置）完美的语法语义一个列表？
Isn't this (and all the other settings) a perfect case semantically for a list?
推荐答案
根据user1474837的有用链接到在这个问题上，似乎很明显，元组用于向后兼容，从一开始就设置完成的方式，这是由于这些元组是由于他们的信念比列表快。 （他们是，但只是非常轻微，根据机票讨论中引用的数据。）
Based on user1474837's helpful link to the Django ticket on this question, it seems clear that tuples are used for backwards compatibility with the way settings were done from the start, which was with tuples due to the belief they were faster than lists. (They are, but only very slightly, according to data cited in the ticket discussion.)
具体来说，Django文档曾经说：
Specifically, Django docs used to say:
在讨论之后，Django核心开发人员注意到：
Later in the discussion, a Django core developer notes:
请注意原始文档中的纯粹一词 - 如果以面值取得意味着指示设置是不可变的，则不是使用元组的原因。还要注意，票证讨论中的某些人将参考设置引用为不可改变，所以甚至不清楚设置实际上是不可变的。
Note the word "purely" in the original documentation -- which if taken at face value would mean indicating settings are immutable is not a reason tuples are used. Also note someone in the ticket discussion references settings as "sort of" immutable, so it's not even clear settings are in fact immutable.
为了感兴趣，请注意票解决方案以：
P.S. For interest, note the ticket resolution ends with:
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